Sectional electric furnace



June so, .1925.

WITNESSES;

1,543,719 W. J. MERTEN SECTIONAL ELECTRIC FURNACE Filed Sept. 20, 1921 l N VENTOR Will/am JM rrem BY ATTORNEY Patented June 30, 1925.

UNITED .S'TA TE'S 3P ATEN T ()F'Ffl C E 41. 13am, 1 or PITTSBURGH, PENNSYLVANIA, ASSIGNOR 'ro =wns'rmc- HOUSE ELECTRIC a MANUMCTURINW comANY, a CORPORATION "OF PENNSYL- 'VAMA.

. smoNAL ELECTRIC FURNACE.-

Applioation filed September 20, 1921. Serial Ito-502,044

'0 all whom it may concern Be itknown that I, WILLIAM J. MERTEN, a citizen of the United States, and a resident of Pittsburgh, in .thecounty of Allegheny :5 and State of Pennsylvania, have inventedra new and useful Improvement in Sectional ElectricFurnaces, of which the following is a specification. 7

My invention relates to naces and particularly to electrical-heat- .troating furnacesand-it has for one of its objects to provide a furnace of relatively simple construction for electrically heating material passed therethrough and having provisions for varying the active length thereof.

"Anotherobject is to provide, adjacent to ,the furnace chamber, a heat-conserving and .materialctoring chamber with means located 0 therein for supporting the heated material.

Another object isto provide means located in said storing chamber for moving the material out of said chamber and elec trically controlled means for'shifting the a heated .material from the supporting means to the ,moving means.

xIn practising my invention, I provide a plurality of walls of any suitable construcimentsilocatedin'the floor, and in'thewalls,

'asw'ell as in the wartitio na'of the furnace. to permit of uniformly .:heating "the entire activejportion of the furnace chamber.

.' I provide aninlet and all-outlet openingv in'two opposing walls of the furnace and locate a charging platform adjaoentrto the inlet opening and a heat eonserving and material-storing chamber adj acent'tothe out- :let-oponing. The'floor of: the furnace chamcharging platform to :the material-storing chamber to permit gravity to move'the marberial through the chamber.

I provide suitable means for supporting [50 the heated material in 'the heat-conserving chamber and further provide means 'within the said chauiberto move the material out of 'rthersame, as may be desired. Electrically controlled means are iprovided, to be gov-' 'erned lby the operator, :toshift the heated heat-treating furmaterial from the supporting means to the moving means.

Inthe single sheet of drawings,

Figure l-is a top plan View of a furnace embodying I my invention theline IL-II ofFig-l, and

Fig. 3 is a fragmentary longitudinal section'of'ya portion of the floor of the furnace. A 'heat treating'furnace, designated generally'by the numeral 10, comprises an-elongated furnace chamber defined by endwalls 11 and 12, side-walls 13 and 14, a floor 15 having .an inclined upper surface and a.

roof 16, all of'which are constructed of such bricks or blocks of heat resisting andheatinsulating material, as are usually employed in the art. Whilel have'illustrated' the-floor 15 as relatively thick, this is not essentiahas it is only necessary that'thethicknessshall be sufiicient to prevent undue loss of heat "therethrough. Asthe round'bars to be heat- :the desiredvalue by the time 'they'have'traversed the chamber.

A charging platform 17, located adjacent toithe'inlet end of the furnace, has asurface inclination or slope corresponding tothat of 'thefloor of the furnace in order that cylin- .(1rical *metal bars to be heat treatedmay move uniformly into and throughthe fur- "nace under the action of gravity. An inlet ropening '18'in 1the wall 13 may be equipped witha'hinged door 19of any suitable con- ;structionand material to substantially close itrias the'material to be'treated'passes-there through. An outlet opening 20 isprovided in the wall '14t0' permit thezheat-treated ma- I 'terial'to leave'the furnace chamber. =her is givenapredeterminedslope "from'the Vertically movable partitions "21 are vpro- .vided at spaced'intervalsito permit of varying the active length of the furnace. fIf relatively short lengths of materialare 'to be heat treated, all of the partition membersmay be in'their lowest positions, whlle, if longer material is to be heat treated, one

or 'mo re of the partitions may be raised until,

if necessary, the entire length of the furnace chamber, or a plurality of separate portions,

*may' be in active use. The vertical'movement of the partitions may be effected in any desired or suitable manner and is not here illustrated in detail as it forms no part of my invention.

Electric heating elements are located in the side and end walls of the furnace chamher and may be of any suitable or desired construction usually employed in furnaces of the above-indicated character. A plurality of resistor members 22, in the form of rods. bars, strands or strips, are located in the floor of the furnace chamber. I have illustrated the construction of the heating element in the floor more particularly in Fig. 8 of the drawing, wherein the resistor members 22 are shown as rods located in the recesses or grooves 23. The ends of the individual resistor members 22 may project outside of the furnace chamber to permit of suitably connecting the members in parallel-circuit or in series-circuit relation with each other.

Electric heating elements 25 are embedded in, or mounted on, each of the surfaces of the partitions 91 and are severally provided with suitable depending contact terminals 26 to engage stationary contact terminals (not shown) when in their normal operative positions.

By employing suitably connected control switches (not shown) it is possible to selectively energize any group of resistors in accordance with the operative length of the furnace. as determined by the movable partitions 21 or in accordance with the separate active portions thereof.

A heat-conserving and material-storing chamber 27 is located adjacent the heattreating furnace 10 at the outlet end thereof and comprises end walls 28, an outer side wall 29 and a roof 31, all of which may be constructed of suitable bricks or blocks of such heat-resisting and heat-insulating material as is usually employed in the art. Partitions 32, located substantially in the same planes as the partitions 21, are provided in the chamber 27 to permit of in creasing the active length of the heat-conserving chamber or of dividing the same in accordance with the active length of the heattreating furnace 10, or its division into separate sections, as hereinbefore described.

A marterial-supporting means is located in the material-storing chamber 27 and comprises a plurality of laterally extending bars 33 suitably secured to longitudinally extending members (not illustrated) to form a unitary rack.

The supporting means is held in its normal operative and raised position by av metal framework 35 controlled by a lever 36 pivotally connected thereto. The lever 36 is maintained in its normal operative position by an electromagnetic device 37, having a winding 38, illustrated only in general in.

Fig. 2. The action of the means 37, the pivoted lever 36 and the members 35 is such that, when the winding 38 is energized from a suitable source of electromotive force (not shown) by momentarily closing a circuit, the outer end of the lever 36 is raised to momentarily lower the supporting means 33, which is returned to its normal raised position as soon as the energizing circuit is interrupted.

A. material-moving means comprises rolls 5! located in laterally spaced relation in the heat-conserving and material-storing chamber 3T. which are tamtinuously rotated by a chain ll which engages sprocket wheels 42 with which the rolls 39 are provided. The entire. set of rolls may be continuously operated by means of a suitable driving motor, (not shown) connected to one of the rolls.

The operation of the heat-treating furnace is suliistant-iully as follows: the furnace being particularly applicable to heating cylindrical metal rods 44 preparatory to being coiled into helical springs or ol. being otherwise operated upon. A plurality of bars or rods 4- may be placed on the charging platform 1'7, from which they move into the chamber of the furnace 10 by reason of the slope of the charging platform and continue to move slowly through thefurnace chamber at such rate as will result in the temperature of the individual bars reaching the desired value by the time they reach the outlet opening 20. The slope of the floor 15 may he. of any suitable degree to permit of obtaining the above described result. \Vhen the heated bars pass out through the outlet opening 20 they rest upon the supporting bars which. in their normal elevated positions, maintain the bars out of operative engagement with the continuously rotating rolls 39. \Vhen the operator desires to remove one or more of the heated bars from the chamber 27 he momentarily energizes the winding 88, thus lowering the supporting means and causing the heated bar or bars to be engaged by the rotating rolls 39 and be moved thereby out of heat-conserving and material-storing chamber 27 to a place or to a machine for further operation thereon.

If it is desired to heat-treat relatively short bars. all of the partitions 21 may be in their lowered positions. and. if it is desired to heat longer bars, one or more of these partitions may be raised to permit of passing the longer bars through the furnace and to permit of heating only so much of the furnace as is required by the lengths of the bars passing therethrough.

Various modifications may be made in the device e'mliiodying my invention without departing from the spirit and scope thereof. and I desire that only such limitations shall be placed thereon as are imposed by the prior art or are specifically set forth in the appended claims.

I claim as my invention:

1. In a heat-treating furnace, in combina tion, an elongated furnace chamber, means for varying the active length of said chamber. electrical heating elements in the floor and walls of said chamber, and a heat-conserving chamber adjacent to said furnace chamber for storing said heated material.

2. In a heat-treating furnace, in combination, a furnace chamber having an inlet and an outlet for material being treated, electric heating elements in the walls of said chamber, a heat-conserving and material-storing chamber adjacent to said furnace chamber, means in said material-storing chamber for su riporting material heated therein, means for moving material out of said storage chamber and electromagnetically controlled means for shifting material from said sup porting means to said moving means.

3. In a heat-treating furnace, in combination, a plurality of refractory walls enclosing a furnace chamber having a sloping floor and an inlet and an outlet opening in said walls. electric heating elements embedded in the walls and floor of said chamber, a chargingplatform adjacent the inlet opening of said chamber, a heat-conserving and materrial-storage chamber adjacent the outlet opening of said chamber, means for supporting heated material in said storage chamber, and electromagnetically controlled means for permitting heated material to be moved out of said storage chamber.

4. In a heat-treating furnace, in combination, an elongated furnace chamber, a plurality of spaced movable partitions for varying the active length of said furnace chamber, electric heating elements in the floor and in the walls of said chamber, and electric heating elements located in said partitions and energized only when the said partitions are in their normal operative positions relatively to said furnace chamber.

5. In a heat-treating furnace, in combination, a plurality of Walls and a floor enclosing-a furnace chamber, electric heating elements in said chamber for heating material passed therethrough, a plurality of spaced movable partitions for varying the active length of said furnace chamber, the floor of said chamber being sloped downwardly to permit of the material being heated to move through said furnace on the floor thereof under the action of gravity.

In testimony whereof, I have hereunto subscribed my name this 17th day of September 1921.

WILLIAM J. MERTEN, 

